Prior to 1974, bulk curing and drying systems included what is referred to as a small or single tier bulk tobacco rack such as shown and disclosed in U.S. Pat. No. 3,105,713 to F. J. Hassler. While the single tier rack was satisfactory and accepted commercially, it did, nevertheless, necessitate significant labor requirements to load each rack individually after the tobacco had been harvested.
Several years ago, Harrington Manufacturing Company of Lewiston, North Carolina, introduced a bulk tobacco curing and drying system that included what is now referred to as bulk tobacco containers or boxes which are adapted to receive field harvested tobacco and to support the same within a barn structure during the curing and drying process. Such a bulk tobacco container or box, as referred to above, is disclosed and shown in U.S. Pat. No. 3,948,553. One of the principal advantages in such a bulk tobacco container or box is that during the harvesting operation, tobacco leaves can be randomly filled directly into the container or box, after which the same container or box is placed directly in a curing and drying structure where the tobacco leaf material therein can be cured and dried. This, obviously, eliminates the retransfer of the tobacco leaves after harvesting as was required with the single tier rack disclosed in the Hassler Patent. Therefore, it can be generally stated that when such containers or boxes are used in conjunction with an automatic tobacco harvester, that substantially all of the hand handling of the tobacco leaves between harvesting and curing and drying is eliminated.
With containers or boxes it still remains important to uniformly load the tobacco therein, and to maintain the uniform distribution of the tobacco leaf material within the container during the entire curing and drying process. As shown in U.S. Pat. No. 3,948,553, referred to above, the containers or boxes are provided with a plurality of tines that extend through the mass of tobacco leaf material within the container, with the tines being supported about the front and back sides of the container when oriented in the curing and drying position. Therefore, it is appreciated that it is the tines that directly support the tobacco leaf material within the container or box.
In some bulk tobacco containers of the type being referred to, it has been found that the piercing ends of the tines sometime fail to locate a back support member for supporting the tines about the back of the container when disposed in the upright curing and drying position. This could be caused by a number of factors. Often as the respective tines are being inserted through the volume of tobacco leaf material they tend to skew at an angle and if the tines are not of sufficient length to reach the back support structure when skewed at such an angle the piercing ends of the tines fail to find support about the back of said container. In addition, if there is insufficient support structure about the back of the container, it then follows that in some cases the tines will not be able to locate a support structure for the piercing ends thereof.
In addition, in rotating the containers from a horizontal filling position to the upright curing and drying position the tines of some containers are proned to move or slide from the normal fully inserted position, causing the piercing ends of the tines to move away from the back support structure and thereby be unsupported. In either of the cases referred to above, the results are the same -- the tobacco leaf material supported by the tines tends to slump, drop, and bunch in areas of the containers giving rise to nonuniform loading. In such cases, problems can be expected because the air during the curing and drying process will tend to pass through the vacated areas of the container, and the areas of high density do not receive sufficient quantities of air to completely dry the tobacco leaf material and consequently the quality of the cured leaf is less than desirable.